This invention relates to a device for avoiding squeaking noises on a window pane, particularly a passenger car side window which can be displaced transversely to a seal resting against the pane.
Self-excited frictional vibrations, which are also known as "slip stick effect", cause squeaking noises when passenger car side windows, which are sealed off with respect to the vehicle body by tight fitting seals, are moved up and down. Generally, it is attempted to avoid the slip stick effect by optimizing of system parameters, such as the mass, stiffness and geometry of the window and seals. As a result of complex friction and damping mechanisms, high-cost theoretical and experimental tests are required for this purpose which, however, do not necessarily guarantee success. Experiments have demonstrated that movements without jerking are possible only in the case of low surface pressures.
A problem which is particularly difficult to solve from an engineering point of view is the squeaking noise which is caused by the sliding of smooth surfaces, such as window panes, on elastic materials, such as seals. Such squeaking noises are particularly annoying in the case of motor-driven passenger car side windows which are moved up or down at a constant speed.
German Patent Document DE 41 19 704 A1 and European Patent Document EP 0 489 537 A1 disclose window seals for passenger car doors in which the contact force of the seal against the pane is reduced during the pane movement, in order to reduce the motor power required to move the pane. Furthermore, velvet-type coverings on seals are known which also reduce the friction, but wear off over time.
From German Patent Document DE 33 01 935 A1 or German Patent Document DE 40 40 037 A1, sealing strips are known which are made of a flexible material into which reinforcing bodies are worked for increasing the flexural strength of the sealing strip or rendering it more durable.
It is an object of the present invention to eliminate the squeaking noises which occur when the window panes, particularly passenger car side windows, are moved up or down, without any impairment of their tightness in the closed condition.
This object is achieved by means of the sealing arrangement according to the invention, in which a window seal is provided in the form of a hollow profile strip that is connected to a vibration damper element.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.